Screening And Appraising Of Drought Sensitive And Dwarf Mutant Lines Induced By Radiation In Developed Upland Rice

The mechanism of drought tolerance is becoming a hotspot in the field of rice molecular worldwide, with the shortage of water resource worldwide and serious drought disaster, research of rice drought resistance are becoming more and more important. We screened and identified drought resistance performance of several drought sensitive mutation lines and one dwarf mutant lines in developed upland rice varieties such as HD616, HD296,HD 44, and HD10 which induced by Co₆₀ γ radiation, and appraised drought resistance of screened mutant lines through anlysis of important agronomic traits and water content physiology in different location ,different years and different drought stress. In the last, we researched the heredity character of drought sensitive mutant lines by crossing drought sensitive mutant lines with their parent.1. Through traits appraise in different years and drought water contrast, We found that there lies great difference between drought sensitive mutant lines and their parent. The mutation lines have more tiller, thin leaf width, low grain weight, thin root are main biological character of these drought sensitive mutant lines.2. When undergone serious drought stress, their prominent characters are slow in growth, serious leaf rool, thin stem and thin leaf, the seed have many drought speckle and low yield.3. Research found drought sensitive mutant lines would decrease their tiller, root number, seed setting rate, yield per plant, increase contrarily .when growth under serious drought stress, they have Less tiller, less root, low seed setting rate, low yield per plant. When growth under paddy land, they shows more tiller, more root, good seed setting rate, high yield per plant. So we draws such conclusion: seed setting rate, yield per plant, and root are important traits related with drought resistance.5. We also studied the heredity of drought resistance by crossing drought sensitive mutant lines with their drought tolerance parent, we found some traits of drought sensitive mutant lines are resessive and some traits are dominant,and tiller are quantity heredity.6. We screened a dwarf mutant lines in IAPAR-9 Co₆₀ γ radiation mutant lines. we found that the dwarf mutant lines performed powerful drought tolerance in serious drought soil condition, we also researched the heredity of dwarf traits of the mutant lines . we found the dwarf mutant lines is sensitive to GA₃ and found its dwarf traits is simple recessive gene. we included that the dwarf gene is an old and founded one .but we think the dwarf mutant lines is a good germplasm in dwarf breeding of upland rice.These drought sensitive mutant lines and dwarf mutant line are very important germplasm in research drought resistance related gene location , drought resistance mechanism.